This invention relates to a no-till fertilizer and seed drill, and in particular to such a drill that ensures that the seed disbursed by the device is positioned a predetermined distance above the fertilizer disbursed by the device upon completion of the process.
No-till drills are commonly used to insert fertilizer and seed into the ground without having to turn the soil and thus destroy the compacting and surface root structure which prevents the soil from being blown away. The use of no-till drills is well known in the prior art. However, no-till drills have shortcomings which have not been completely overcome by the prior art, even though a concerted effort has been made to eliminate these shortcomings.
A first shortcoming of no-till drills relates to the inability to place the seed in the soil above the fertilizer and to maintain this separation after the soil is packed back over the seed and fertilizer. This separation is necessary to prevent seedlings which are produced from the seed from being burned by the fertilizer. A chronology of typical prior art attempts to overcome this shortcoming is set forth in a series of patents issued to Ivyl D. Kopecky. In Kopecky, U.S. Pat. No. 4,417,530, an attempt to create this separation is made by positioning the exit of the seed supply tube above and behind the exit of the fertilizer supply tube and then relying on soil falling on top of the fertilizer before the seed is deposited. This system depends a great deal on soil characteristics and is inconsistent at best. In Kopecky, U.S. Pat. No. 4,565,141 a sealer plate is placed between the fertilizer supply tube and the seed supply tube in order to manually cover the fertilizer with soil before the seed is deposited. While the use of a sealer plate provides more consistency than merely relying on the soil falling into place over the fertilizer, it also is inconsistent and depends on the makeup of the soil. Since the seed is deposited directly behind the fertilizer, a substantial portion of it drops into close proximity to the fertilizer irrespective of any packing which is accomplished by the sealer plate.
In Kopecky, U.S. Pat. Nos. 4,674,419 and 4,607,581 the sealer plate is refined to improve its packing efficiency and to form grooves on either side of the main furrow that is formed by the blade of the device. The seed tube also is divided into two portions which are angled outwardly from one another so that seed is deposited into the two grooves. Because the divided seed tube transversely separates the seed from the fertilizer, the device shown in Kopecky '419 and '581 does a good job of keeping the seed separated from the fertilizer when it is operated on flat terrain. However, when this device is operated on transversely sloping terrain the seed deposited from the seed tube on the uphill side falls directly behind the fertilizer and this separation is not maintained. The result is that the Kopecky '419 and '581 device is no more effective at maintaining fertilizer and seed separation on transversely sloping ground than are the earlier devices.
Another shortcoming of the prior art no-till seed and fertilizer drills also occurs when the devices are used on transversely sloping terrain. After the seed and fertilizer have been inserted into a furrow, the furrow is closed and compacted by a packer wheel which is pulled behind the drill assembly. Typically, several drill assemblies and packer wheels are carried side by side on a common wheeled frame and when such a device is used on transversely-sloped terrain it will tail or become cocked at an angle with respect to the direction of travel so that the downhill side of the frame is ahead of the uphill side. Since the packer wheels are mounted behind the frame and are rigidly connected to it, the packer wheels become offset from the furrows when tailing occurs. Thus, packing is not accomplished as well on transversely sloping terrain as it is on flat terrain.
The subject invention overcomes the first shortcoming of the prior art by mounting a seed distribution assembly behind the upper portion of a chisel blade which is used to create a furrow in the soil that is being planted. The seed distribution assembly includes a horizontal seed distribution plate having an upwardly turned lip at its rear edge and vertical side walls attached to each of its sides. The side walls extend from the blade rearwardly over less than the entire extent of the seed distribution plate, so as to create a closed ended trough between the blade, the seed distribution plate, and the side walls. The seed distribution assembly is wider than the blade and is located on the blade is such that it is partially in and partially out of the furrow created by the blade. As a result, the seed distribution assembly causes the upper portion of the furrow to be made wider than the lower portion.
The fertilizer supply tube extends below the bottom of the seed distribution assembly and thus causes the fertilizer to be deposited in the bottom of the furrow. The seed supply tube, on the other hand, exits into the trough which is located above the seed distribution plate. Seed therefore accumulates in the trough until the trough becomes partially full, and then flows off of the sides of the seed distribution plate between the lip at its end and the side walls. As a result the seed falls onto the ledges which are formed between the upper and lower portions of the furrow and, accordingly, remains separated from the fertilizer even when the furrow is closed by the packer wheel. When the device is used on transversely sloping ground the seed distribution plate becomes tilted and the seed only drops off of its downhill side where it falls onto the downhill ledge in the furrow. Thus, even on sloped terrain all of the seed remains separated from the fertilizer.
The second shortcoming is overcome by mounting the packer wheel on a bar which is rotatable relative to the shank which carries the blade and seed distribution assembly. This allows the packer wheel to rotate so that it remains parallel with the direction the device is being pulled even when the seed drills are angled downhill because a plurality of them are mounted on a common wheel frame which is traveling across transversely-sloped terrain. Since the furrows formed by the blades also are parallel with the direction the device is traveling the packer wheels remain centered on the furrows and completely cover and compact them.
Accordingly, it is a principal object of the present invention to provide a no-till seed and fertilizer drill which maintains a predetermined amount of separation between the fertilizer and the seed.
It is a further object to provide such a no-till drill which forms a furrow that is wider at its upper portion than at its lower portion and which deposits the seed on a ledge which is formed between the upper and lower portions of the furrow.
It is a still further object of the present invention to provide such a no-till drill which has a packer wheel that remains aligned with the furrow it is to pack even when the device travels across transversely sloping terrain.
The foregoing and other objectives, features and advantages of the present invention will be more readily understood upon consideration of the following detailed description of the invention taken in conjunction with the accompanying drawings.